Some broadcast signals (e.g., frequency modulation (FM) radio broadcast signals) include, typically limited amounts of, embedded data. For FM radio broadcasts, an example communication protocol used to carry embedded data is radio data system (RDS), or radio broadcast data system (RBDS), which is the United States (U.S.) version of RDS. Example embedded information includes time, station identification, program information, etc.
Audience measurement entities (AMEs) perform, for example, audience measurement, audience categorization, measurement of advertisement impressions, measurement of media exposure, etc., and link such measurement information with demographic information. AMEs can determine audience engagement levels for media based on registered panel members. That is, an AME enrolls people who consent to being monitored into a panel. The AME then monitors those panel members to determine media (e.g., television programs or radio programs, movies, DVDs, advertisements (ads), streaming media, websites, etc.) exposed to those panel members. In this manner, the AME can determine exposure metrics for different media based on the collected media measurement data.